When people add a definition to urban dictionary, usually on music, movies or sometimes even books (In the case of Twilight), and attempt to brain wash people in to believing their opinion is fact, even though it's usually moronic.
Example of Urban Opinions.
Example 1; All Time Low
your stupid if you dont check them out."
Example 2; Twilight
"You should read the Twilight books and see the movie, they are all great"